Guys, guys, hold your horses, please. Don't you think that if there were room in the spacer for all those things, there would be no need for the spacer in the first place? Or was that the point? Am I being obtuse?

__________________In particle accelerators atoms are indeed not only touching each others. But banging together in a massive explosive orgasm.
-- nieldk in a TMO post

Guys, guys, hold your horses, please. Don't you think that if there were room in the spacer for all those things, there would be no need for the spacer in the first place? Or was that the point? Am I being obtuse?

I believed there was actually a lot of space in there, but apparently I understood something wrong back in the days when the idea of the spacer came up. I thought the spacer was needed only because one component (modem? Don't remember) could not fit on the PCB within N900 thickness, but that the extra thickness provided by the spacerframe was not used over the whole area.

Sorry for the misunderstanding. I jumped in after the post I quoted in my previous message.

[Edit] Joerg_rw, don't know if that will be possible on the Neo900, but on my N900 I can manage to store an extra µSD on top of the currently used µSD, just by shifting it a little so the bump does not stack. No noticeable extra pressure on the back cover.

I think you were perfectly right :-) despite the "original rationale for needing the spacerframe" is also correct, it been intorduced by modem module height, but meanwhile we crammed in so much that we used up pretty much all of the additional space

There are enough GPIOs for 1 bit operation, or if you use some of the UART signals as GPIOs, then there are enough signals for regular 4 bit operation.

The regulated supply voltage available on Hackerbus will probably be 2.7 V, which is just at the lower end of the standard SD card voltage range.

Finding a nice place for the card holder would be more of a challenge. I guess there should be sufficient room if you remove the camera. Else, some creativity may be needed :-) When looking for such a place, the scans and photos here may help:https://neo900.org/stuff/werner/scans/